fix(server): fix Kafka Streams metric values should be returned with …

…content-type text/plain (#125) Resolves: #125
streamthoughts · Mar 2, 2021 · 36f0bb0 · 36f0bb0
1 parent 3bdaadb
commit 36f0bb0
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Showing 2 changed files with 14 additions and 3 deletions.
diff --git a/azkarra-server/src/main/java/io/streamthoughts/azkarra/http/ExchangeHelper.java b/azkarra-server/src/main/java/io/streamthoughts/azkarra/http/ExchangeHelper.java
@@ -28,6 +28,7 @@
 import io.undertow.util.Headers;
 import io.undertow.util.StatusCodes;
 
+import java.math.BigDecimal;
 import java.nio.charset.StandardCharsets;
 import java.util.Deque;
 import java.util.Map;
@@ -126,6 +127,16 @@ public static void sendJsonResponseWithCode(final HttpServerExchange exchange,
         exchange.getResponseSender().send(JSON.serialize(response), StandardCharsets.UTF_8);
     }
 
+    public static void sendTextValue(final HttpServerExchange exchange, final Object value) {
+        final String s = value instanceof Double ?
+                new BigDecimal(value.toString()).stripTrailingZeros().toPlainString()
+                : value.toString();
+        exchange.getResponseHeaders().put(Headers.CONTENT_TYPE, "text/plain");
+        exchange
+                .setStatusCode(200)
+                .getResponseSender().send(s, StandardCharsets.UTF_8);
+    }
+
     private static Optional<String> getFirst(final String name,
                                              final Map<String, Deque<String>> parameters) {
         Deque<String> parameter = parameters.get(name);

diff --git a/...server/src/main/java/io/streamthoughts/azkarra/http/handler/StreamsGetMetricsHandler.java b/...server/src/main/java/io/streamthoughts/azkarra/http/handler/StreamsGetMetricsHandler.java
@@ -45,6 +45,7 @@
 import static io.streamthoughts.azkarra.http.ExchangeHelper.getOptionalQueryParam;
 import static io.streamthoughts.azkarra.http.ExchangeHelper.getQueryParam;
 import static io.streamthoughts.azkarra.http.ExchangeHelper.sendJsonResponse;
+import static io.streamthoughts.azkarra.http.ExchangeHelper.sendTextValue;
 import static io.streamthoughts.azkarra.http.utils.Constants.HTTP_QUERY_PARAM_FILTER_EMPTY;
 import static io.streamthoughts.azkarra.http.utils.Constants.HTTP_QUERY_PARAM_FORMAT;
 import static io.streamthoughts.azkarra.http.utils.Constants.HTTP_QUERY_PARAM_FORMAT_VALUE_PROMETHEUS;
@@ -111,9 +112,8 @@ public void handleRequest(final HttpServerExchange exchange) {
                 throw new MetricNotFoundException("{group=\"" + group.get() + "\"}");
             }
 
-            boolean extractValue = exchange.getRelativePath().endsWith("/value");
-            if (name.isPresent() && extractValue) {
-                sendJsonResponse(exchange, metric.get().value());
+            if (name.isPresent() && exchange.getRelativePath().endsWith("/value")) {
+                sendTextValue(exchange, metric.get().value());
             } else {
                 sendJsonResponse(exchange, groupSet);
             }